Overview

Comprehensive Description

Description

Esperiopsis fucorum is an intense reddish orange encrusting soft sponge, which becomes colourless in alcohol. The body shape is highly variable amongst individuals (extremely polymorphic) and individuals are fast growing, changing shape within a few weeks. Growth forms include thin sheets, cushions, massive-lobose or branched. It can also occur in hollow 'amphora' shaped forms in sheltered conditions.Pigment can be squeezed out between the fingers. The sponge is thought to go colourless in deeper water. Has also been found growing up hydroid stems.

This sponge coats the stems of Tubularia for the length of seven inches, at no part exceeding two lines in thickness. Its general aspect in the dried state is rough and irregular in consequence of the prominent hispidation of its surface, produced by the prolongation of the primary lines of the skeleton beyond the dermal membrane, frequently to the extent of the length of two or three times that of a spiculum. The oscula are not visible without the aid of a lens of an inch focus. The construction of the skeleton is very irregular and diffusive, and the secondary lines especially, and to such an extent as to frequently render it difficult to decide whether they are really secondary skeleton lines or dispersed skeleton spicula. The skeleton spicula are regularly acuate and rather slender. The retentive spicula are not visible in a fragment of the sponge immersed in water, and it is only when mounted in Canada balsam that they can be distinctly seen in situ in the dermal membrane, on which they are not equally dispersed, but occur in clusters at intervals. In the interstitial membranes they are very few in number, and rarely more than one occurs in the field at the same time.

There is a considerable degree of resemblance in the descriptions of I. Alderi and I. paupera to that of I. Edwardii, which may possibly lead to a doubt in the mind of the student as to which of the three the specimen he might have under examination belonged; but a comparison of the spicula alone of these three species readily distinguish each from the other. The length of the spicula of I. Edwardii as compared with those of both I. paupera and I. Alderi is as seven to five, and although thus much longer, the diameter is less than either of the spicula of the other two species, and the form is much more purely acuate.”

Article rating
from 0 people

Description

This bright orange sponge is extremely polymorphic and fast growing, changing shape in just a few weeks. It may be encrusting as thin sheets or cushions, massive lobose, with or without tassels, or branched. The encrusting form of this species may be confused with other orange/red encrusting sponges but the soft texture and open surface are quite distinctive.

Article rating
from 0 people

Esperiopsis fucorum occurs in the shallow sublittoral zone, often overgrowing the holdfasts of Laminaria sp. or sessile invertebrates. It can tolerate a wide range of exposures and can also be found in areas experiencing strong tidal currents. Occasionally found in cryptic low-littoral habitats.

Article rating
from 0 people

This species is common on the low shore and shallow sublittoral, it is seldom found in the circalittoral zone. It occurs in a wide range of habitats from extremely sheltered to extremely exposed and also under a wide range of current regimes.